>>>Go Further: Understanding the Numerical Values

Regular sliders have numerical values associated with them; the 0 point is almost always in the center of the slider. Dragging the bar to the left moves that slider’s parameter into negative (or reduced) territory, and dragging the bar to the right moves that slider’s parameter into positive (or enhanced) territory. The numerical values displayed along with a slider’s bar position signify the exact level of adjustment made. The numerical values run from –1.00 to 1.00 for every sub-slider except for the Black & White Intensity and Grain sliders, where it ranges from 0.00 to 1.00; the Sharpen Intensity, Edges, and Falloff sliders, where it ranges from 0.00 to 1.00; the Definition slider where it ranges from 0.00 to 1.00; the Noise Reduction slider, where it ranges from 0.00 to 2.00; the Vignette Softness slider, where it ranges from 0.00 to 1.00; the Warmth slider, where it ranges from 0.00 to 1.00; the Temperature slider, where it ranges from 2500 to 10,000; and the Tint slider, where it ranges from –50.00 to 50.00. In general, these numerical values are not important to any but the most professional photographer.

>>>Go Further: Understanding Light Level Adjustments

Before you play around with the light levels in your photos, it’s important to understand what each sub-slider in the Light tool does:

• Exposure: Move this slider to adjust the overall lightness of a photograph. Unlike the button sliders found later in the Levels tool, which adjust individual light tones, midtones, or dark tones, the Exposure slider adjusts all tones evenly. Drag it to the right of the 0 marker to increase a photo’s brightness, or drag it to the left of the 0 marker to decrease its brightness.

• Highlights: Use this slider to reduce or enhance the brightness of highlights in your photo. In other words, it reduces or enhances only the bright areas (such as a bright sky) so you can see less or more detail in them (such as wisps of clouds). Drag the bar to the right of the 0 marker to increase a photo’s highlights, or drag it to the left of the 0 marker to decrease its highlights.

• Shadows: Use this slider to reduce or enhance the shadows in your photo so you can see more detail in a dark area. For example, in a photo of a person in a black shirt, the shirt might look like a solid, almost formless, mass of black. Using the shadows slider, you can bring out the details in the shirt, such as the ripple in its fabric. Drag the bar to the right of the 0 marker to enhance a photo’s shadows, or drag it to the left of the 0 marker to reduce its shadows.

• Brightness: Move the Brightness slider to lighten or darken your image by affecting the midtone pixels in the image the most. Drag the bar to the left to make the overall image darker or to the right to make it brighter.

• Contrast: The contrast of a photo is the amount of difference between the light and dark areas in it. A high-contrast photo has a sharper divide between light and dark. A low-contrast photo has a less jarring divide. Drag the bar to the left to have less contrast or to the right to have more contrast.

• Black Point: A black point is a small area of an image that is maximum, or true, black—that is, not just a little black or “almost totally black,” but as black as black can be. Use the slider to increase or decrease the value of the black point. Decreasing the value causes more detail to be seen in the shadow areas. Increasing the value causes less detail to be seen in the shadow areas.

>>>Go Further: Understanding the Color Tool

Before you play around with the color levels in your photos, it’s important to understand what each sub-slider in the Color tool does.

• Saturation: Adjust the Saturation slider to change the color richness, or intensity, of the photograph. By default, the Saturation slider is set at 0.00, which is neutral. When you drag the slider to the left, you decrease the intensity of the colors in your photo. If you drag the slider all the way to the left, down to –1.00, the photo becomes black and white. Conversely, dragging the slider to the right increases the intensity of the colors of your photo. If you drag the slider all the way to 1.00, the colors in your photo look quite nuclear, as if they are radiating light.

• Contrast: Use this slider to affect the color contrast of a photo, or the difference between “warm” colors—such as shades of yellow, orange, red, and pink—and “cool” colors—such as violet, purple, blue, and green. Using the contrast slider, you can make the image’s colors less contrasted by dragging the bar to the left or more contrasted by dragging the bar to the right.

• Cast: A photo’s color cast refers to the tint of a photogrpah. Photos shot indoors often have an orange hue that you might want to eliminate. Alternatively, photos taken in shadow can look too blue. Also, an entire photo can be tinted blue or orange if there is a lot of that particular color in the photograph. Drag the Cast slider to the left to make it “cooler” by increasing the blue tint and reducing the orange tint. Drag the Cast slider to the right to make it “warmer” by increasing the orange tint and reducing the blue tint.

>>>Go Further: Working in Black and White

Although you can turn a color photo black and white by using the Saturation sub-slider in the Color tool, Photos includes a dedicated Black & White adjustment tool to give you even greater control.

Before you do work with the Black & White tool, it’s important to understand what each of the tool’s sub-sliders does:

• Intensity: The Intensity slider controls the overall intensity of white and blacks applied to the image. Drag it to the left and the image will have more gray and less black in it. Drag it to the right and the image will have more black in it.

• Neutrals: This slider adjusts the strength of the midtones, or grays, in the photograph. Drag this slider to the left and the image’s midtones lighten. Drag it to the right and the image’s midtones darken.

• Tone: This slider adjusts the picture to give it a higher or lower contrast look. Drag this slider to the left to lighten the image. Drag it to the right to darken the image.

• Grain: Before the days of digital photography, photographs where recorded on film using chemicals. Depending on the type of film used, the photograph could have a more grainy appearance. (Think of black-and-white movies from the 1940s.) Use the grain slider to give your photographs an old-timey feel.

>>>Go Further: Working with the Sharpen Tool

When you edit a digital photo, the adjustments you make to its contrast or exposure can sometimes cause edges to become softer, or blurred. You can use the Sharpen tool to fix the blurred edges so they show up more crisply in photos. Note that you cannot use the Sharpen tool to fix a photo that was taken out of focus.

The Sharpen tool has three sliders:

• Intensity: Use this slider to adjust the overall amount of sharpening applied to edges. Drag the bar to the right to make the edges of objects in the photo more crisp, or sharp. Drag it to the left to reduce the crispness of edges in the photo.

• Edges: Use this slider to control which pixels in a photograph Photos considers edges and which it does not. Dragging the Edges slider to the right increases the number of pixels that Photos should recognize as edges, thus making more objects in your photograph more defined. Dragging the Edges slider to the left decreases the number of pixels that Photos should recognize as edges.

• Falloff: All digital images are made of pixels. The Sharpen tool uses these differing pixels to distinguish between the edges of objects in your photograph. The tool “reads” the edges at a declining rate, aplying less sharpening adjustment to each subsequent pixel. Adjust the Falloff slider to control the amount of sharpening that is applied to the pixels as they get further away from the first pixel’s edge. For example, if you set this slider to the 0.60 mark, only 60% of the sharpening adjustment applied to the edge’s first pixel is applied to subsequent pixels.

>>>Go Further: Working with Vignettes

A Vignette is a circular shading applied to the edges of your photo. Vingettes can be used for any reason you like, but many times photographers apply them to call out the subject of the image. The Vignette tool has three different sliders. Here’s what each one does:

• Strength: Use this slider to adjust the strength of the vingette’s shadow. Drag the slider to the right to make the shadow stronger or darker. Drag the slider to the left to make the shadow weaker, or even totally white.

• Radius: Use this slider to adjust the radius of the vingette. Drag it to the right to increase the radius, which means the vingette covers more of the image. Drag it to the left to decrease the radius, so the vingette sticks closer to the edges of the image.

• Softness: Use this slider to adjust the softness of the edges of the vingette. Drag it to the right to have the vingette gradually fade out as its radius increases. Drag it to the left to give the vingette a stark contrast from the rest of the image.

>>>Go Further: Working with the Eye-dropper Tool

Sometimes the lighting in a photograph makes the subject appear to have unnatural skin tones—perhaps too orange or yellow. Sometimes the lighting also makes an object in an image—such as a wedding dress—appear less white than it should be.

You can correct these color errors by using an eye-dropper tool that tells Photos that a certain pixel color in your image should indeed be pure white or have more natural skin tones. When you click the affected area of the image, Photos knows that it needs to correct that area and not only adjusts all of that specific color in the image, but subtly adjusts every other color in the image to give it a more accurate rendering.

In addition to the Eye-dropper tool, the White Balance tool has three other sliders that enable you to adjust the overall color tempurature of the image:

• Warmth: This slider is only visible when Skin Tone or Natural Gray is selected from the drop-down menu by the eye-dropper tool. Warmth refers collectively to the color cast (the tempurature plus tint) of the colors in a photograph. Drag the Warmth slider to the left to make it “cooler” by increasing the blue and green and reducing the orange and red. Drag the Warmth slider to the right to make it “warmer” by increasing the orange and red and reducing the blue and green.

• Temperature: This slider is only visable when Temperature/Tint is selected from the drop-down menu by the eye-dropper tool. In a photograph, temperature refers to color temperature, or the warmth and coolness of the colors in a photograph. Drag this slider to the left to make the image more blue, or to the right to make the image more orange.

• Tint: This slider is only visable when Temperature/Tint is selected from the drop-down menu by the eye-dropper tool. Tint refers to the reds and greens in your photo. Drag this slider to the left, making the image more green, or to the right, making the image more red.

>>>Go Further: Working with Levels

The Levels tool looks almost exactly like the histogram, discussed earlier in this chapter, with the exception that is has multiple sets of markers. Each marker is a slider that you can drag and adjust. The features of the Levels adjustment tool enable you to manually adjust the tonal values of the shadows, midtones, and highlights of an image, and it gives you the abiliy to color correct your image by adjusting the levels of the red, green, and blue channels together or independently.

The primary markers in the tool are the most significant ones, each with a different color in its center. The marker on the left is the black point (tone), the marker in the middle is the gray point (tone), and the marker on the right is the white point (tone). You use these markers as sliders to adjust the black, gray, or white points of a photo.

The next set of markers are the Quarter-Tone markers. There are two of them—one between the black and gray point markers and one between the gray and white point markers. These give you additional control over the tonal values between your image’s shadows and midtones and between your image’s midtones and highlights.

The final set of markers are the three triangles that run along the top of the Levels tool; they control the brightness of an image. With the center one you adjust the brightness of an image uniformally. With the left marker you adjust the brightness of only the shadows, and with the right marker you adjust only the brightness of highlights.

The Levels tool also features a channel button that reveals the option to control the luminance levels of your photo without affecting its color cast; the option to control the entire Red, Blue, and Green (RBG) specturm all at once; and the options to control the red, blue, and green spectrums individually.